Running an on-page SEO audit does not always require paid tools. In this guide, we explain how to manually audit every key on-page SEO factor for any article or web page — using free tools and simple techniques that any marketer or website owner can apply immediately.
On-Page SEO Audit Checklist
Before diving into each step, here is a quick overview of what to check in a complete on-page SEO audit:
- Focus keyword in Title, URL, and Meta Description
- Focus keyword in the first paragraph and last paragraph
- Headings and subheadings
- Image alt tags and captions
- Keyword density (keep under 2% for long-tail keywords)
- Content uniqueness (aim for 80–100%)
- Keyword decoration (bold and italics)
- External links and internal links
- Article length
Check Focus Keyword in Title, URL, and Meta Description
Search for your focus keyword on Google and look at the top-ranking results. Check whether the keyword appears in the title, URL, and meta description of that page. You can use the site: operator (e.g., site:yourwebsite.com "focus keyword") to verify this for your own pages. Alternatively, press Ctrl + U to view the page source and use Ctrl + F to search for your meta title, meta description, and URL slug.
Check Focus Keyword in First and Last Paragraph
Open your article and manually check whether your focus keyword appears naturally in both the opening paragraph and the closing paragraph. This is a standard on-page best practice that signals relevance to search engines from the beginning and end of your content.
100% Placement Support
Get Placed After Your Digital Marketing Course at DVA Coimbatore
Resume building, interview prep, and direct company tie-ups. Real placements, not promises.
Check Keyword Density
For long-tail keywords, keep keyword density below 2%. You do not need to worry as much about single-word or two-word keyword density. Use one of these free tools to check:
- SEOReview Tools — free keyword density checker
- Small SEO Tools — keyword density analyzer
Check Domain Authority and Page Authority
Domain Authority (DA) indicates how well a site can rank based on its backlink profile. Use a free tool like Website SEO Checker to check DA and PA. Higher DA generally correlates with better ranking potential, so building quality backlinks is important for long-term SEO growth.
Check for Plagiarism
Google penalizes pages with duplicate or copied content. Aim for at least 80% unique content. Check plagiarism using these free tools:
- Small SEO Tools
- Duplicate Checker
You can also manually check by copying a paragraph from your page, pasting it into Google surrounded by quotation marks, and seeing whether the same content appears elsewhere.
Check Internal and External Links
Best practice: include at least 2 external links per article, ideally with rel="nofollow" for outbound links to non-partner sites. Internal links help search engines understand your site structure and pass authority between pages. Use Small SEO Tools or Duplicate Checker to audit links, or manually right-click each link and select Inspect to verify where it points.
Check Image Alt Tags
Search engines cannot read images — they rely on alt text to understand what an image shows. Check that every image on your page has a descriptive alt tag that includes your focus keyword where relevant. To verify: press Ctrl + U to view page source and search for img src, or right-click the image and click Inspect.
Recommended Free On-Page SEO Audit Tools
- Seobility — comprehensive on-page audit
- Sitechecker Pro — technical and on-page analysis
- SEO Site Checkup — on-page elements checker
- Small SEO Tools — multiple individual checkers